Flat shielded cable termination method and structure



Aug. 19, 1969 H. w. RICHTER ,5

FLAT SHIELDED CABLE TERMINATION METHOD AND STRUCTURE Filed Oct. 9, 1967 II I2 I FIG. 2

HERMAN W RICHTER INVENTOR.

ATTORNEYS United States Patent US. Cl. 174-88 21 Claims ABSTRACT OF THE DISCLOSURE The shielding conductor laminae at the terminal ends of a flat shielded cable are separated from the signal conductor lamina, and one of the shielding conductor laminae is folded around the edge of the signal conductor lamina and into alignment with the other shielding conductor lamina. The terminal ends of the laminae are trimmed and stripped of insulation to bare extending ends of conductors which are soldered to a terminal board. Preferably, the folding is arranged to bring the extending ends of normally registering shielding conductors into contact at one side of the terminal board for soldering, and the signal conductors into contact with conductors on the opposite side of the terminal board for soldering. Also, the laminae are preferably mechanically bonded to the terminal board for strain relief.

This invention relates to a termination method and arrangement for a flat shielded cable.

The objects of the invention include, without limitation, a flat shielded cable termination arrangement that is simple, economical, fast, secure, neat, requires little time or labor to make, and orients conductors in the most convenient manner for easy identification.

These and other objects of the invention will be apparent hereinafter from the specification which describes the invention, its use, operation, and preferred embodiments and procedures, from the drawings, which constitute a part of the disclosure, and from the subject matter claimed.

Generally, the inventive termination method and arrangement is used for flat shielded cables having a central lamina containing a plurality of laterally spaced, parallel signal conductors and a corresponding plurality of shielding conductors in each of a pair of outer laminae secured to opposite faces of the central lamina so that a pair of shielding conductors is registered with each signal conductor. According to the invention at least one of the outer laminae are separated from the signal conductor lamina at the terminal end of the cable, and a separated one of the shielding laminae is folded around the side edge of the signal conductor lamina and brought into adjacent alignment with the other shielding conductor lamina. Such folding is preferably accomplished to bring respective normally registering shield conductors for each signal conductor into contact at the terminal end of the cable. The preferably exposed ends of all the conductors are then joined to approriate conductors on a terminal member, preferably with the shielding conductors and the signal conductors joined to opposite sides of the terminal member.

In the drawings:

FIG. 1 is a plan view of the terminal end of a flat shielded cable suitable for use in the invention;

FIG. 2 is an end elevation of the cable of FIG. 1;

FIG. 3 is a perspective view of the inventive termination arrangement for a flat shielded cable;

FIG. 4 is an end elevation of the termination arrangement of FIG. 3; and

3,462,542 Patented Aug. 19, 1969 FIG. 5 is an exploded, partially cut-away, perspective view of the inventive termination arrangement.

Flat shielded cable 10, as best shown in FIGS. 1 and 2, is formed with four signal conductors 11-14 in a central lamina 15 that has an upper lamina 16 and a lower lamina 17 secured to its opposite faces. Lamina 16 contains four shielding conductors 21-24 in registry with signal conductors 11-14 respectively, and similarly, lower lamina 17 includes four shielding conductors 31-34 in registry with respective signal conductors 11-14. Laminae 16 and 17 are preferably bonded to central lamina 16 in such a Way that the three laminae can be readily separated at a terminal end, Depending upon which of several generally known means are used for securing laminae 15-17 together, heat or solvents can be used to facilitate separating outer laminae 16 and 17 from central lamina 15.

Cable 10 is terminated according to the invention by securing all its conductors to terminal member or board 18 as described more fully below. The completed cable termination is best shown in FIGS. 3 and 4. The preferred arrangement of terminal members 18 and laminae 15-17 to accomplish the inventive termination is best illustrated in the exploded view of FIG. 5.

All the conductors 11-14, 21-24, and 31-34, are preferably bared by stripping away the insulation at the terminal end of cable 10, and preferably laminae 16 and 17 are each separated from lamina 15 as illustrated. The terminal board 18 has four shield conductor strips 41-44 arranged on its upper surface and four signal conductor strips 51-54 arranged on its lower surface. The terminal board 18 is preferably disposed over the upper surface of lamina 15 with its conductors 51-54 in contact with the bared ends of respective signal conductors 11-14.

Lower lamina 17 is preferably folded back on itself at a transverse fold line 25 normal to the direction of lamina 17. An oblique fold 26 at preferably at 45 angle to the direction of lamina 17 is then formed to lead lamina 17 to the edge 27 of lamina 15. Lamina 17 is then bent around the edge 27 of lamina 16 with either a single curved bend of a pair of sharp transverse folds 28 and 29 each normal to the direction of lamina 17. Another oblique fold 30 also, at preferably a 45 angle to the direction of lamina 17 is made to bring lamina 17 into alignment with lamina 16. In folded condition, the lines of oblique folds 26 and 30 are preferably parallel.

With such an arrangement conductors 31-34 of lamina 17 are registered with and engaging adjacent conductors 21-24 of lamina 16. Each pair of shielding conductors 21-31, 22-32, 23-33, and 24-34, are then brought respectively into contact with shield conductor strips 41-44 of terminal member 18 and soldered together preferably by reflow soldering. At the same time, signal conductors 11-14 are soldered to conductor strip 51-54.

Preferably at the same time such soldering is accomplished, laminae 15-17 are mechanically bonded to each other and to opposite face surfaces of terminal board 18 for strain relief. Heat, solvents, adhesives, or other fastenings can be used to accomplish such a mechanical bonding which secures the termination securely to the termination board and prevents cable tension from breaking the solder connections.

With such an arrangement, all the conductors maintain their lateral orientation in the termination. Thus, each of the shielding conductors 21 and 31 normally in registry with signal conductor 11 are soldered to terminal board 18 at the same side of the terminal board that such conductors occupy in cable 10. Signal conductors and shielding conductors can thus be readily identified by noting their termination position from a side of the cable.

Although top and bottom have been used in referring to the drawings as illustrated, the inventive terminating arrangement can be used on a variety of cables oriented in any convenient way. For simplicity, four sets of conductors have been shown in the illustrated cable, but any convenient number of conductors can be used within the spirit of the invention. Moreover, cables with more than three laminae can be folded and terminated according to the invention; either shielding or signal conductor lamina can be folded around either edge of a cable; and more than one laminae can be folded around either edge of a cable in forming an inventive termination. Also, signal and shielding conductors need not have the relative sizes and shapes as those illustrated.

Oblique folds 26 and 30 can be turned in either direction so that lamina 17 is either folded over or under for each relative fold. Also, lamina 17 can be bent around the edge 27 of lamina 15 and inserted under rather than over lamina 16 as illustrated. Furthermore, for applications in which it is not necessary to keep shielding conductors associated with each respective signal conductor, reversing fold 25 can be omitted. Also, reversing fold 25 can be located in several positions in the folding sequence, and the folded lamina can be turned with each fold so as to make one full turn or twist if desired.

With the laminae properly folded and aligned in place the soldering of the shielding conductors and the signal conductors to terminal board 18 can be accomplished in a single operation. If the folding is done neatly, a compact and simple termination such as illustrated in FIG. 3 results, and it will be seen that the inventive termination arrangement accomplishes the objects of the invention.

The preferred order of steps in the inventive method are: cutting the cable to provide a terminal end; separating at least one of the shielding conductor laminae and folding it into alignment with the opposite laminae according to the invention; trimming the laminae so they all terminate in a single line; stripping away insulation to bare the ends of the conductors; positioning the conductors in contact and registry with the terminal board; and reflow soldering the assembly in a single operation. Of course, soldering can be done in separate steps, and trimming and stripping steps can be done in some other order. The termination board is preferably mechanically bonded between two laminae of the cable at the same time the soldering is accomplished to provide strain relief for the termination.

I claim:

1. A termination arrangement for a flat, shielded cable having a central lamina of insulating material containing a plurality of laterally spaced Signal conductors and a pair of outer laminae of insulating material secured to opposite faces of said central lamina, said outer laminae each containing a plurality of laterally spaced shielding conductors, said termination arrangement comprising:

(a) separation of at least one of said outer laminae from said central lamina for a distance from a terminal end of said cable;

(b) a plurality of transverse folds in a separated one of said outer laminae;

(c) said folds being arranged for leading said folded lamina laterally around a side edge of said central lamina and into adjacent alignment with the other of said outer laminae;

(d) a terminal member; and

(e) means for joining said signal conductors and said shielding conductors to said terminal member.

2. The termination arrangement of claim 1 wherein said folds include two folds oblique to the direction of said folded lamina.

3. The termination arrangement of claim 2 wherein the lines of said oblique folds are substantially parallel to each other in folded condition.

4. The termination arrangement of claim 3 wherein said shielding conductors and said signal conductors extend beyond said insulating material and said folds are .4 arranged to bring said extending ends of normally registered shielding conductors into contact in said alignment.

5. The termination arrangement of claim 4 wherein each of said outer laminae are separated from said central lamina for a distance from said terminal end of said cable, said terminal member includes a first plurality of conductors in a first plane, and a second plurality of conductors in a second plane, and wherein said shielding conductors are joined to said first plurality of conductors in said first plane, and said signal conductors are joined to said second plurality of conductors in said second plane.

6. The termination arrangement of claim 5 wherein said laminae are bonded to said terminal member.

7. The termination arrangement of claim 1 wherein each of said outer laminae are separated from said central lamina for a distance from said terminal end of said cable, said terminal member includes a first plurality of conductors in a first plane, and a second plurality of conductors in a second plane, and wherein said shielding conductors are joined to said first plurality of conductors in said first plane, and said signal conductors are joined to said second plurality of conductors in said second plane.

8. The termination arrangement of claim 7 wherein said laminae are bonded to said terminal member.

9. The termination arrangement of claim 1 wherein said folds include a transverse fold normal to the direction of said folded lamina to bend said folded lamina back on itself and two oblique folds of approximately 45 to the direction of said folded lamina, the lines of said oblique folds being substantially parallel in folded condition.

10. The termination arrangement of claim 9 wherein said folds include a transverse fold normal to the direction of said folded lamina to bend said folded lamina around said edge of said central lamina.

11. A method of terminating a flat shielded cable having a central lamina of insulating material containing a plurality of laterally spaced signal conductors and a pair of outer laminae of insulating material secured to opposite faces of said central lamina, said outer laminae each containing a plurality of laterally spaced shielding conductors, said terminating method comprising:

(a) separating at least one of said outer laminae from said central lamina for a distance from a terminal end of said cable;

(b) folding a separated one of said outer laminae around a side edge of said central lamina and into adjacent alignment with the other of said outer laminae; and

(c) joining said signal conductors and said shielding conductors to corresponding respective conductors on a terminal board.

12. The method of claim 11 including trimming said laminae to terminate in a line in folded condition.

13. The method of claim 11 including stripping said insulating material from the terminal ends of said laminae to bare extending ends of said shielding and signal conductors.

14. The method of claim 11 including bringing normally registered shielding conductors into contact in said alignment.

15. The method of claim 14 including separating each of said outer laminae from said central lamina for a distance from said terminal end of said cable, joining said shielding conductors to corresponding respective conductors in one plane on said terminal board, and joining said signal conductors to corresponding respective conductors in another plane on said terminal board.

16. The method of claim 15 including bonding said laminae to said terminal board.

17. The method of claim 15 including stripping said insulating material from the terminal ends of said laminae to bare extending ends of said shielding and signal conductors.

18. The method of claim 11 wherein said folding of said outer lamina includes forming a fold oblique to the direction of said folded lamina, leading said folded lamina to the edge of said central lamina, bending said folded lamina around the edge of said central lamina, and forming another fold oblique to the direction of said folded lamina to bring said folded lamina into said alignment with the other of said outer laminae.

19. The method of claim 18 wherein said folding additionally includes forming a transverse fold normal to the direction of said folded lamina to bend said folded lamina back on itself.

20. The method of claim 11 including heating said terminal end of said cable before separating said outer laminae.

References Cited UNITED STATES PATENTS 2,963,535 12/1960 Wegener et al. 17436 10/1961 Stearns. 1/1967 Basile.

DARRELL L. CLAY, Primary Examiner US. Cl. X.R. 

